I suggest to validate your JSON in an online JSON validator like jsonlint for better info where the problem lies.
Also, as mentioned in this SO post and this SO post, that leading 0
's on a number would also cause this kind of issue.
If you have a number, don't ever store it with leading zeroes. If you
have a value that needs to have a leading zero, don't treat it as a
number, but as a string. Store it with quotes around it.
Here is an example:
Invalid
{
"attribute": "// numeroConta",
"operator": "=",
"value": 0030152201
}

Valid
{
"attribute": "// numeroConta",
"operator": "=",
"value": "0030152201"
}

Please provide your settings.json
if this is not the case.